CVE-2026-49837

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Source
https://cve.org/CVERecord?id=CVE-2026-49837
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-49837.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-49837
Aliases
Downstream
Related
Published
2026-09-10T21:56:13Z
Modified
2026-09-12T03:46:39Z
Severity
  • 5.9 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N CVSS Calculator
Summary
GoBGP: BGP OPEN capability parser may read capability values outside declared CapLen boundaries
Details

GoBGP is an open source Border Gateway Protocol (BGP) implementation in the Go Programming Language. Versions prior to 4.6.0 contain a BGP OPEN capability parsing issue where several concrete capability decoders may parse data from the full remaining capability buffer instead of the slice bounded by the declared capability length, CapLen. A malformed BGP OPEN message can cause bytes from a following capability to be interpreted as part of the current capability. The most security-relevant case is the 4-octet AS capability, where a capability with CapLen == 0 may cause the parser to read bytes from the following capability as the 4-octet AS value. This parsed value may later affect peer AS validation during BGP session establishment. Version 4.6.0 patches the issue.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-125"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49837.json"
}
References

Affected packages

Git / github.com/osrg/gobgp

Affected ranges

Type
GIT
Repo
https://github.com/osrg/gobgp
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
f02ca397821f6ca182ef4eb492c3cbc459552d7c
Database specific
Show details 
{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "4.6.0"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "REFERENCES"
    ]
}

Affected versions

v1.*
v1.0
v1.1
v1.10
v1.11
v1.12
v1.13
v1.14
v1.15
v1.16
v1.17
v1.18
v1.19
v1.2
v1.20
v1.21
v1.22
v1.23
v1.24
v1.25
v1.26
v1.27
v1.28
v1.29
v1.3
v1.30
v1.31
v1.32
v1.33
v1.4
v1.5
v1.6
v1.7
v1.8
v1.9
v2.*
v2.0.0
v2.1.0
v2.10.0
v2.11.0
v2.12.0
v2.13.0
v2.14.0
v2.15.0
v2.16.0
v2.17.0
v2.18.0
v2.19.0
v2.2.0
v2.20.0
v2.21.0
v2.22.0
v2.23.0
v2.24.0
v2.25.0
v2.26.0
v2.27.0
v2.28.0
v2.29.0
v2.3.0
v2.30.0
v2.31.0
v2.32.0
v2.33.0
v2.34.0
v2.4.0
v2.5.0
v2.6.0
v2.7.0
v2.8.0
v2.9.0
v3.*
v3.0.0
v3.0.0-rc1
v3.0.0-rc2
v3.0.0-rc3
v3.0.0-rc4
v3.1.0
v3.10.0
v3.11.0
v3.12.0
v3.13.0
v3.14.0
v3.15.0
v3.16.0
v3.17.0
v3.19.0
v3.2.0
v3.20.0
v3.21.0
v3.22.0
v3.23.0
v3.24.0
v3.25.0
v3.26.0
v3.27.0
v3.28.0
v3.29.0
v3.3.0
v3.30.0
v3.31.0
v3.32.0
v3.33.0
v3.34.0
v3.35.0
v3.36.0
v3.37.0
v3.4.0
v3.5.0
v3.6.0
v3.7.0
v3.8.0
v3.9.0
v4.*
v4.0.0
v4.1.0
v4.2.0
v4.3.0
v4.4.0
v4.5.0

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-49837.json"